Workshop Summary: Rickettsial Genetic manipulation: thinking out of the box Rickettsial diseases are significant causes of morbidity and mortality. They are responsible for the majority of hospital admissions, intensive care admissions, and fatalities among all tick-borne infections. Many are emerging or re-emerging, have biothreat implications, and are highly neglected. Rickettsial diseases were responsible for the loss of millions of lives and were second only to malaria as the cause of febrile illness among troops in World War II, the Korean War, and the Vietnam Conflict. No vaccine for any rickettsial disease exists, and interactions of these bacteria with their arthropod vector and mammalian hosts ? their extended genomes ? is fertile ground for investigating both host and parasites/symbionts. A major knowledge gap is the limited capacity for genome manipulation of these bacteria, forestalling efforts that could rapidly advance understanding of pathogenetic mechanisms and the creation and implementation of countermeasures for disease prevention, as highlight in the 2011 Institute of Medicine of the National Academies workshop report, ?Critical needs and gaps in understanding, prevention, amelioration, and resolution of Lyme and other tick- borne diseases?. The complex challenge of preventing rickettsial diseases is due, at least in part, to the evolutionary relationships between the etiologic agents, their arthropod vectors, and mammalian hosts. An expanded repertoire of Rickettsiales genomes illustrates the diversity of the various genera and species, but the lack of their tractable genetic manipulation hinders a deeper comprehension of the significance of genome diversity. The American Society for Rickettsiology (ASR) has a long history of providing forums that foster scientific interactions and rich intellectual exchange among world-renowned experts on rickettsial diseases, and welcomes complementary input and opinion from leaders in related fields such as chlamydiology, or among those who study intracellular parasitism in a broader sense. The 29th Meeting of the ASR will be held June 8-12, 2018, at the Hyatt Regency Milwaukee in Milwaukee, Wisconsin. Approximately 200 attendees representing junior and established scientists from academia, government, and industry are anticipated. The conference's overarching goal is to advance knowledge and stimulate interactions among these researchers through lectures, short oral presentations, poster sessions, and networking opportunities. To address the aforementioned knowledge gap, we propose a small workshop within the framework of the 29th meeting entitled, ?Rickettsial Genetic manipulation: thinking out of the box.? The workshop's aims are to (i) provide a forum that promotes scientific exchange among participants and experts through invited keynote and plenary lectures, short talks, and posters by leaders and junior investigators who study rickettsial and obligate intracellular bacteria ? pathogens or not; (ii) offer a program that presents the latest, cutting-edge research of rickettsial and other diseases caused by obligate intracellular pathogens, with a bias toward those transmitted by arthropod vectors; (iii) provide a venue that fosters intellectual exchange and networking opportunities between junior and senior investigators; and (iv) promote participation by early career investigators and trainees who are underrepresented in the biomedical sciences, including women. Efforts will also be made to accommodate attendees in need of child care. Support for the workshop is requested to cover the cost of coordination, facilities, travel expenses for invited speakers and selected attendees ? primarily early career scientists and trainees, and for audio-visual services and program production.